Diaphragm-pump.



Patented July 11, 1916.

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W. C. CARTER.

' mAPHHAGM PUMP.

APPLICATION FILED DEC. 7, 1914.

UNITED sTATEs PATENT OFFICE.

WILLIAM C. CARTER, 0F ST, LOUIS, MISSOURI.

DIAPHRAGM-PUMP.

Application led December 7, 1914.

To all whom t may concern.'

Be it known that I, IVILLIAM C. CARTER, a citizen of the United States, residing at St. Louis, Missouri, havel invented a certain new and useful Improvement in Diaphragm- Pumps, of which the following is a full, clear, and exact description, such as will enable` others skilled in the art to which it appertains to make and use the same.

This invention relates primarily to diaphragm pumps, although one feature of my invention consists in/a fuel supply device of novel design that is similar in construction and principle of operation to the fuel supply apparatus disclosed in my prior Patent No. 1,146,133, dated July 13, y1915.

One object of my present vinvention is to provide a diaphragm pump which is so designed that the diaphragm chamber of the pump will be absolutely cut off from the pressure line after the diaphragm has moved in one direction, thereby preventing the diaphragm from being subjected to vabnormal pressure after it has performed its function.

Another object is to provide a diaphragm pump that is equipped with a valve, controlled by the diaphragm that closes automatically, and thus cuts olf communication between the diaphragm chamber of the pump and the pressure line after pressure sufficient to actuate the diaphragm has entered the diaphragm chamber.

Another object is to provide a diaphragm pump which is so constructed that when it is used in connection with an internal comtional vie-w of a fuel supply device and diaphragm pump constructed accordance with my invention. Fig. 2 is a detail sectional view taken on the line 2-2 of Fig. 1; and Fig. 3 is a detail view, illustrating a slight modification of my invention.

Referring to Fig. vl of the drawings which illustrates the preferred form of my invention, A designates the casing of my im- Specication of Letters Patent.

Patented July 11, 1916.

serial No. 875,942.

proved pump, which is preferably formed from two disk-shaped members whose peripheral edge portions are securely connected together in any suitable manner, as, for example, by means of rivets l. inside of the casing A, which I will term the diaphragm chamber, is divided into two compartments by means of a diaphragm B that consists of a disk-shaped member whose peripheral edge portion is securely clamped between the two members that constitute the casing A of the pump. One side of the casing A communicates with a pressure line 2 in which the pressure rises and falls intermittently, and the otherk side of said casing communicates with a device that the pump operates. I have herein illustrated my improved pump as 'being used in connection with an internal combustion engine for drawing a charge of liquid fuel from a source of supply and forcing it into a tank or reservoir from which the liquid fuel is conducted to the carbureter of the engine, but I wish it to be understood that the pump is not limited to this use or to use with an internal combustion engine, for it can be used for various other purposes and in connection with any kind of a compressing device or pressure line in which the pressure The space rises and falls intermittently, and thus causes the diaphragm of the pump to vibrate back and forth.

In' the apparatus herein shown the pressure line 2 that communicates with one side of the diaphragm chamber of the pump leads to one of the cylinders of an internal combustion engine or to the exhaust pipe of the engine, not shown, and the opposite side of said diaphragm chamber communicates with a valved passageway that is arranged between a liquid fuel supply pipe 3 and a tank or reservoir C which is provided at its lower end with a discharge pipe 4: that leads to the carbureter of the engine.

' When "the diaphragm B of the pump moves in one direction a check valve 5 that acts as the inlet valve for said passageway will open automatically, and thus permit liquid fuel to be drawn into said passageway from the supply pipe 3 by the suction created in. said passageway, by the movement of.the diaphragm of the pump. When the diaphragm of the pump moves in the opposite directionv this charge of fuel that was drawn into the valved passageway by the preceding movement or suction stroke of the diaphragm will be forced out of said passageway into the fuel tank C through a discharge port that is normally closed by a discharge valve 6.

In the diaphragm pumps that have heretofore been in general use, so far as I know, the diaphragm chamber was either in direct communication with the pressure line that operated the pump or av gravity-operated valve provided with an inlet opening was arranged between the diaphragm chamber and the pressure line. Consequently, when such pumps were used in connection with internal combustion engines the diaphragme were soon rendered unfit for use, by reason of the high pressure and the hot gases and the carbon coming in direct contact with the diaphragme, this, of course, being due to the fact that the diaphragms were subjected to the direct action of the explosions in the engine. In order to overcome this objectionable feature I have provided my improved pump with means controlled by the diaphragm tor cutting off communication between the diaphragm chamber and the pressure line after suflicient pressure has entered the diaphragm chamber to move the diaphragm in one direction. When the pump is used in connection with an internal combustion engine said means prevents the diaphragm from being subjected to the direct action of the explosions in the engine,

`and it also prevents the hot gases and carbon from coming in Contact with the diaphragm. Furthermore, it prevents the diaphragm from being subjected to abnormal pressure, this being true whether the pump is used in connection with an internal combustion engine or with any other type of compressing device. The means that I pre- :ter to use for accomplishing this consists of a valve D arranger-l between the pressure .line 2 and the diaphragm chamber of the pump and constructed in such a manner that it will be held in its open position by the diaphragm and will close automatically before the pressure in the pressure line 2 reaches a high degree. Said valve D is provided with a stem 7 that passes loosely through a port in a valve casing 8 that is connected to one side of the casing A ot the pump, the valve casing S of the pump herein shown being provided with a reduced screw-tlireawled portion 8L that is screwed into one side of the pump casing at the center of same. The stem 7 of the valve D is provided with one or more longitudinally extending grooves 'ia that establish communication between the pressure line Q and the diaphragm chamber of the pump when the valve D is open. Said valve stem 7 is preferably so proportioned that when the valve D is seated, as shown in Fig. 1, the inner end of the stem 7 will bear lightly upon the diaphragm B of the pump. In the embodiment of my invention herein shown the diaphragm is imperforate, or, in other words, 1s not provided with an orifice through which a gas or liquid could pass from one side of the diaphragm to the other side of the diaphragm and the valve stem 7 is not rigidly connected to the diaphragm, thus producing a pump that is particularly well adapted toi-pumping gasolene and other volatile liquids. lVhen the diaphragm is flexed in or. direction it bears against the inner end or' the stem 7 and thus holds the valve D unse-ated so that the pressure can enter the diaphragm chamber quickly and actuate the diaphragm. lVhen the pressure liexes the diaphragm in the opposite' direc tion, the valve D Jfollows the diaphragm and moves to its closed position. The outward movement of the valve D is limited by means of a' stop 9, against which the head of the valve D strikes when said valve is moving to its open position. The diaphragm B is moved in one direction, to the left, looking at l? ig. 1, by the pressure in the pressure line 2, and said diaphragm B is moved in the opposite direction by means of a spring 10 that is arranged inside ot a nipple ll which projects laterally from one side of the casing A ot' the pump, the d1aphragm B being preferably provided with a boss or projection l2 that tends to center the spring 10 and cause it to bear evenly upon the Adiaphragm B of the pump.

lhen the engine is in operation the diaphragm B vibrates back and forth in the manner previously described, the movement ot said diaphragm to the right, looking at Fig. l, being effected by the spring l0, and the movement of said diaphragm to the left being eii'ccted by the pressure in the pressure line Then the diaphragm B moves to the right, under the influence of the spring 1l), the pressure that it exerts against the stem of the valve D causes said valve to open. Said valve remains in its open position, due to the pressure that the diaphragu'i exerts thereon, during the first portion of the compression stroke of the piston oi the particular cylinder of the engine to which the pressure line 2 leads. The pressure that is developed in the pressure line 9 during the first part of the compression stroke ot the piston is exerted on the diaphragm B of the pump. and consequently, will impart a power ihipulse to said diaphragm, or, in other words. cause it to move to the left, looking at Fig. l. it, of course, heilig understood that at this time the grooves or grooves T in the stem of the valve D, which is open, establish conmmnication between the pressure line Q and the diaphragm charnber of the pump and permit suiiicient pressure to enter said chamber to actuatc the diaphragm quickly. When the pressure iu the pressure line '2 reaches a certain degree suitable material b, as shown in Fig. 1, thethe valve D will close, and thus completely cut of communication between the diaphragm chamber of the pump and the pressure line 2. The groove or grooves Ta in the stein of the valve D are so proportioned that said valve will move at such a speed that it will be closed by the time the diaphragm B has reached its limit of movement to the left: In other words, the groove or grooves 7a in the stem f the valve D are just large enough so that only sufficient pressure to actuate the diaphragm will enter the diaphragm chamber of the pump before the valve D closes, the subsequentrise in pressure in the pressure line 2 having no eect upon the diaphragm B, in view of the fact that the diaphragm chamber is then absohitely cut off from the pressure line.' When the pressure in the line 2 drops, the spring 10 moves the diaphragm B of the pump in the opposite direction and also restores the valve D to its open position. From the foregoing it will be seen that the valve D closes before the explosion in the cylinder of the engine occurs and remains closed until the pressure in the line 2 drops or diminishes suihciently to permit the spring 10 to restore the diaphragm to its normal position. Consequently, the diaphragm of the pump is not subjected to the direct force of the explosion in the engine, and there is no possibility of the hot gases and carbon coming in direct contact with same, and thus damaging or destroying the diaphragm.

The diaphragm B of the pump may be formed in variousways and from any suitable material. It is preferably built up of several layers of sheet material so as to form a laminated diaphragm. One type of diaphragm that I have found to be very efficient is made from a single sheet 'of fibrous or nonmetallic material a arranged between two thin sheets of copper or other fibrous material that I prefer to use being known commercially as Seigelite and consisting of a woven fabric thatis not affected by gasoleiie. The fiber (t will not break or lose its elasticity, even after it has been subjected to long continuous use and the layers or sheets of metal that incase the fiber protect saine froni any moisture that might enter the diaphragm chamber, and thus cause the fiber to warp if it were n ot pro-A tected, the layers of sheet metal that cover the fiber being sufiiciently thin so that they will not he broken by the constant vibrations of the diaphragm back and forth.

In F ig. 3 I have illustrated another type:V

e clamped together and arranged in such a.

manner that the grain in the metal of onc sheet or layer crosses thc grain of the metal in the other sheets or layers between which it is arranged.

The complete fuel supply device, of which my improved pump forms a part, is of novel design. in that a spring 6a is employed for normally holding the discharge valve 6 seated, and means are provided for closing the air vent opening 13 at the upper end of the fuel reservoir C when the fuel in said reservoir rises above a certain level, due to the pressure that the source of supply exerts on the fuel in the reservoir C when the automobile on which the device is used is traveling down an incline. A float 14 that is arranged inside ofthe fuel reservoir C is securely connected to a rod 15 whose lower end projects into a hollow valve stem 6b on the discharge valveG, said rod being provided with a head 1G that strikes against the upper end of the valve stein Gb, and thus raises said valve from its seat when the fuel in the reservoir C rises above a certain level. A spider or stop 17 that is connected to the rod 15 forms a stop or abutment for the upper end of the valve spring 6, and thus causes said spring to exert sufficient tension on the valve 6 to hold saine closed, even though the float 14 rises and falls as the level of the fuel in the tank C varies. The upper end of the rod 15 supports a ball check valve 18 that moves upwardly and closes the air vent 13 when y the source of supply of liquid fuel becomes vthe fuel to flow from said reservoir to the carbureter through the discharge pipe 1 at` the lower end of the reservoir C. Normally the aii vent 13 is open, even when the float 14 rises high enough to unseat the discharge valve 6 and cut off the supply of fuel to the reservoir from the passageway between ythe valves 5 and 6, because the distance between the head 16.011 the rod 15 and the upper end of the valve steni 6b is less than the distance between the check valve 1S and its seat. In other words, the ioat 11 can risc high enough to unseat the valve (3 and cause the supply to the reservoir C to be cut off without causing the air vent 13 to be closed. It is only when the source of supply of fuel is arranged in a higher level than the valves 5 and (i that the float 14 will rise high enough to cause the valve 1S to close the air vent 13, but as the supply of fuel is then exerting pressure on the fuel in the reservoir, the fuel can How freely from the reservoir to the carbui-eter.

`/I-Iaving thus described in v invention. what v` claim. and desire to secure. by Letters Patent` is:

1. A diaphragm punip provided with an iinperforate liaphragin that is adapted to be moved in one directionby the pressure in a pressure line, a housing in which said diaphragm is arranged, one side of said housing communicating with a chamber or passageway through which the material being pumped passes, and means controlled by the diaphragm for preventing the diaphragm Jfrom being subjected to greater pressure than that which was required to move it after said diaphragm has moved in one dircction.

A diaphragm pump provided with an imperiorate diaphragm and with means controlled by the diaphragm for preventing the supply ot pressure that operates the diaphragm trom entering the diaphragm chamber ot the pump after the diaphragm has been moved in one direction.

Il. A diaphragm pump provided with a diaphragm chamber, one side of which has an opening that communicates with a pressure line in which the pressure rises and lalls intermittently and the other side communicating with a passageway through which the material being pumped passes, an impertorate diaphragm in said chamber, and means controlled by the diaphragm for absolutely cutting od communication between said diaphragm chamber and pressure line a i'ter the diaphragm has been moved in one direction by the pressure in said line.

4. A diaphragm pump that is adapted to be operated by an expansible medium, said pump being provided with means controlled by the diaphragm for causing the supply of exl'iansible medium that actuates -the diaphragm to be absolutely cut off from the diaphragm chamber of the pump after said diaphragm has been moved in one direction, said means consisting of an element separate and distinct from the diaphragm and which can more independently of the diaphragm.

ln a diaphragm pump that is adapted to be operated by an expansible medium, an imperiorate diaphragm, and a valve that is held in its open position by the diaphragm, said valve being arranged between the diaphragm and the supply ot' pressure that opcrates the diaphragm and being adapted to be closed auionuitically by said pressure a l'ler the diaphragm has been moved in one direction by the pressure which entered the diaphragm chmnber of the pump.

l. A diaphragm pump, comprising a casing. a diaphragm arranged inside of same, a .spring arranged on one side of said diaphragm for moving it in one direction, means wherehv an expansihlc medium will act upon said diaphragm to more it in the opposite direction, and means governed by said dialihragm `l'or cutting off communication between the diaphragm and the source oll suppl)Y of said expansible medium after said diaphragm has been moved by said expansible medium.

7. A diaphragm pump provided with a. diaphragm which is adapted to be moved in one direction bythe pressure of an expansible medium, a valve arranged between the diaphragm and the supply of expansible medium that actuates said diaphragm, said valve being held in its open position by said diaphragm and being adapted to close automatically andthus cut off communication between the diaphragm chamber of the pump and the pressure line after the diaphragm has been moved by said expansiblel medium, and a spring for moving said diaphragm in the opposite direction and for opening said valve.

8. A diaphragm pump provided with an imperforate diaphragm, a pressure line for supplying pressure to operate the diaphragm, an imperforate valve that is a.r ranged between the diaphragm of the pump and said pressure line and which is held in an inoperative position by the diaphragm, said valve being adapted to move independently of the diaphragm and being so constructed that it will be closed automatically by the pressure in said line and thus cut ott all communication between said pressure line and the diaphragm after the diaphragm has moved in one direction.

9. In a diaphragm pump of the type that is adapted to be operated by the pressure of an expansible medium supplied through a pressure line, an imperforate diaphragm, an imperforate pressure-operated valve that is arranged between the diaphragm and the pressure line that operates the pump so as to cut ofi' communication between said diaphragm and pressure line, a part provided with a port, and a stem on said valve loosely mounted in said port and being so constructed that the pressure can pass through said port and actuate the diaphragm before theV pressure in said line becomes great enough to cause said valve to close, the inner end of said stem normally bearing against one side of the diaphragm.

l0. A diaphragm pump provided with a pressure supply passageway, an imperforate valve for cutting off all communication hetween said passageway and the diaphragm chamber of the pump, an imperforate diaphragm in said chamber, a stem on said valve arranged in said passageway and bearing against one side of the diaphragm of the pump, and means whereby the pressure can pass through said passageway into the diaphragm chamber of the pump and operate the diaphragm before the pressure in said passageway becomes great enough to cause said valve to close.

11. A diaphragm pump provided with an imperforate valve for cutting ott all communication between the diaphragm chamber of the pump and the pressure line that operates the pump, said valve being moved to communication between the in said line, means for openlng the valve,

means for limiting the opening movement of the valve, ,and an' imperforate diaphragm that governs the closing of'said valve.l

13. A diaphragm pump comprising a casing, an imperforate diaphragm arranged in'- side of said casing, one side of said casing communicating with a pressure line, and an imperforatey pressure-operated valve arranged between said diaphragm and pressure line and provided with a stem whose inner. end bears against one side of the diaphragm, thereby causing the diaphragm to govern the closing of the valve, said valve being so constructed that it will -close automatically and thus cut 0H communication between the diaphragm and pressure line when the pressure in said line reaches a certain degree after the diaphragm has been flexed in one direction.

14. A diaphragm pump, comprising a casing, a diaphragm arranged inside of said casing, one side ofsaid casing-communicating with a pressure line, an imperforate valve arranged between said diaphragm and pressure line and provided with a 'stem whose inner end bears ./against the diaphragm so that the diaphragm will govern the opening and closing of said valve, said valve being so constructed that it will close automatically and thus out off communication between the diaphragm and pressure line when the pressure in said line' reaches a certain degree after the diaphragm has been moved in one dlrection, rand a spring arranged on the opposite side of the diaphragm that restores the diaphragm after it has been actuated by the pressure insaid line, and which also causes the valve to move to its open position.

15. A diaphragm pump provided with a diaphragm formed .from a sheet of fibrous ,material, and sheets of metal arranged on opposite sides of said brous material so as to protect same.

16. A fuel supply device, comprising a liquid fuel tank, a valved passageway arranged between said tank and a source of supply of liquid fuel, an inlet valve for said passageway for controlling the admiion of` the liquid fuel into same, an youtlet valve for said passageway for controlling the flow. of the liquid fuel into said tank, a spring that normally holds said outlet valve seated,

outlet valve.

17. A fuel supply device for internal combustion engines provided with a'liquid fuel tank, a-valved passageway arranged intermediate said tank and a supply of -liquid fuel, said passageway 'being provided with an inlet valve that governs the, admission of the liquid fuel to said passageway and also having a discharge valve that governs the flowof the fuel from said passageway into said tank, a spring that normally exerts and means for automatically unseating said pressure on said discharge valve, a float in WILLIAM o. CARTER.`

Witnesses:

WELLS L. CHURCH, 'GEORGE BAKEWELL. 

